1. Field of Invention
The present invention relates generally to interactive broadcast systems, such as interactive cable systems, and more particularly, to systems an methods to manage the response capacity of an interactive broadcast system.
2. Background of the Invention
Interactive broadcast systems generally provide the viewer with various levels of interactivity associated with broadcast programs. This interactivity may include purchasing items advertised or sold during broadcast programs, registering the viewer with a service provided by a cable or broadcast operator, requesting additional information to be transmitted to the viewer, and the like. To provide these types of interactivity, the interactive broadcast system includes some mechanism for receiving responses created by viewers at their broadcast receivers. Conventionally, these responses are either stored in the broadcast receiver, and uploaded to the cable head-end on a polling scheduling, or are directly provided back to the cable head-end by a backchannel, such as a telephone line connection.
Systems of the former type are currently the most prevalent ones in use. In these systems, the broadcast receiver stores the viewer responses in a local memory. The cable head-end polls each of the broadcast receivers in the system, typically once each day late in the evening, and reads the stored responses from the local memory.
The total amount of response data that can be accumulated in this fashion is limited by several constraints. The communications network that couples the cable head-end to the broadcast receivers has a fixed bandwidth, which will vary in each cable system. This bandwidth, combined with a maximum amount of time allowed to conduct the polling each night (e.g., 1-2 hours), determines the total amount of response data that can be collected each night. The total number of responses may then be estimated by dividing the total amount of response data by the average amount of data per response. If more than the maximum number of response or data is stored in the broadcast receivers for uploading during a polling period, the excess responses are simply lost and not captured. Loss of responses is generally an unacceptable outcome, since those responses may be purchases or other important responses that both the viewer and the broadcaster (e.g., product advertiser) expect to be received.
A separate issue from the response capacity of the broadcast system is the amount of memory in each of the broadcast receivers. The installed base of broadcast receivers typically have between 100 and 1000 bytes of memory available to store responses. Conventionally, once a response is written it cannot be modified or removed until the broadcast receiver is polled. Thus, this very small amount of memory requires efficiency in how responses are structured. Even so, the typical response requires about 50 bytes, limiting these devices to between 2 an 20 responses per polling period. In addition, different responses often have different data requirements. Simple acknowledgments may require a very small amount of response data, while a purchase response may require significantly more data, such as a viewer's name, address and billing information. Typically, the broadcast receiver will attempt to store each response the viewer generates, but this may result in the loss or failure to capture responses beyond the memory capacity of the broadcast receiver. Conventional systems provide no mechanism for the broadcast receivers to dynamically reconfigure themselves to selectively or preferentially store different types of responses.
Accordingly, it is desirable to provide a system and method for managing the response capacity of an interactive broadcast system.